Starting current is important for the correct selection of protection and understanding the condition of the motor. Let's look athow to check the starting currentand what deviations mean.
What is starting current
At the moment of starting, the engine consumes a current 5-7 times more than the rated current, since the stationary rotor does not yet create a back-EMF. As acceleration progresses, the current drops to operating level.
How to measure
- Current clamp meters with a peak fixation function (Inrush).
- Measurement at the moment of starting at idle and under load.
- Comparison with the rated current from the nameplate.
What they are talking about deviations
| Result | Conclusion |
|---|---|
| 5–7 times the nominal | Normal |
| Time-long start | Overload, weak network, broken rotor rods |
| Very high and sharp | Possible jamming, short circuit |
Why is this needed
Knowing the starting current allows you to correctly select machines, cables and starting equipment so that the protection does not trigger falsely. A slow start-up indicates problems that diagnostics reveals. To reduce the starting current, use a soft start or a frequency converter.
Is the engine difficult to start or knocks out the protection when starting in Tashkent? Elektromotors engineers will take measurements and select a solution - leave a request.